K&N maintains testing facilities in the USA, the UK and the Netherlands. These facilities incorporate both airflow and horsepower/torque testing capabilities. Our horsepower/torque testing is performed on wheel-based dynamometers, which measure actual brake horsepower and torque at the wheel(s) receiving power from the drive train. This is different and we believe more realistic than horsepower/torque testing done at the flywheel of an engine because the power lost between the engine and the wheels does not contribute to the power needed to put a vehicle in motion. Our standard horsepower/torque testing is designed to measure relative power differences on a vehicle with and without K&N products installed. Our horsepower and torque numbers use SAE (Society of Automotive Engineers) correction factors. We attempt to hold all other variables constant to generate a reliable measurement of changes in horsepower and torque on a vehicle before and after a K&N product is installed.
Airflow testing is a little more complicated, so we have included a detailed description of our airflow testing protocol on another page.
To test the Dust filtration efficiency for a particular air filter, we use both an independent lab and our own dirt retention laboratory to conduct such tests in accordance with the ISO 5011 testing procedure.
Power Gain Charts
Because of some of the unbelievable claims of power gains made by other manufacturers of air filters and intake systems, we feel it is important that our performance claims are realistic and that they are clearly explained. The vehicles our R&D department uses for testing are loaned to us by consumers residing near our test facilities.
Some of our intake kits have power gain charts, which show actual Dyno run plots. These plots show the median run of a specific vehicle, which had three runs with the original stock intake system and three runs with the K&N intake kit installed. The year, make, model, and engine type of the vehicle tested is shown on each chart. The ambient temperature and atmospheric pressure at the time of the run is printed on the chart along with the correction factor. The correction factor is used by the Dynometer to calculate the horsepower and torque relative to standard conditions. This correction factor helps to ensure that our power gain measurements are accurate and that the gains shown are not affected by changes in environmental conditions. We believe these power gain results are representative of the power similar vehicles should realize. Due to the uniqueness of each vehicle, there are occasions when a vehicle will experience a much larger or much smaller power gain than other identical model vehicles. While some of these power gains are incredible, we will not use a Dyno run that depicts an unrealistic increase in power.
Mechanical testing performed at one of our testing facilities supports all horsepower and torque claims advertised by K&N. Horsepower and torque claims are based on testing of an actual vehicle on a dynamometer before and after a K&N product has been installed. Airflow claims are based on tests performed in accordance with our own testing protocol in a dust-free environment on laboratory equipment. Filtration efficiency claims are based on tests performed in accordance with testing procedure ISO 5011. We believe these tests form a reliable basis for performance claims measuring relative differences in the results being compared. These claims are the result of specific tests performed on a given date. Your results will vary based upon such things as atmospheric and weather conditions, vehicle make, model, equipment, or condition, and the K&N part number in use. Our products are designed to provide increased performance and we are confident you will enjoy your K&N experience.
Specific testing documents that support any particular claim are available upon written request.